ABSTRACT
Curcumin is a natural polyphenolic compound that exhibits strong antioxidant and anticancer activities; however, low bioavailability has restricted its application in chemotherapeutic trials. The present study aimed to investigate the anticancer effect of the novel curcumin derivative 2E,6E2(1Hindol3yl) methylene)6(4hydroxy3methoxy benzylidene)cyclohexanone (IHCH) on A549 lung cancer cells. Cells were treated with IHCH at different concentrations (140 µM) for different time periods (136 h). Microscopic analysis revealed that IHCH inhibited A549 cell growth and induced the formation of characteristic autophagolysosomes in a dose and timedependent manner. Furthermore, the inhibitory rate of IHCH (40 µM) on A549 cell viability was 77.34% after 36 h of treatment. Acridine orange staining revealed an increase in autophagic vacuoles in the IHCHtreated A549 cells. Monodansylcadaverine staining was used to analyze autophagy rate. Immunocytochemistry revealed an increase in light chain (LC) 3 protein expression in the IHCHtreated cells and western blot analysis detected the conversion of LC3I to LC3II, as well as the recruitment of LC3 to autophagosomes in the cytoplasmatic compartment, suggesting the occurrence of autophagy. These findings show that IHCH induced autophagy in A549 cells, which is a novel cell death mechanism induced by curcumin derivatives.